There might be some concerns (eg. "wow gold mining is dirty, we should do something about it"), but I personally haven't seen anything close to "we should ban gold".

because gold is useful, bitcoin only has speculative value

This is addressed in a sibling comment. https://news.ycombinator.com/item?id=26089473

And gold is useful.

Almost half of the world gold demand is for speculative/investment purposes[1]. If you consider jewelry to be speculative as well (at least partially, since if you only cared about appearance you could just plate it), the vast majority isn't "useful".

[1] https://www.statista.com/statistics/299609/gold-demand-by-in...

> Almost half of the world gold demand is for speculative/investment purposes

fair (and I think gold as a "beautiful" metal is dumb), but the other half of the usage (on your claim) is for an array of productive things. I don't see wires, heat reflectors, etc being made out of bitcoin.

>but the other half of the usage (on your claim) is for an array of productive things

It's far less than that. Only 7.48% is definitely useful (under "technology").